He told MIPTV: "There is something kind of wonderful about this role, in that I climb from a relatively dark, little, nasty corner into a global spotlight, and look to morph myself to accommodate that stage.

"It's... about someone who is recognizing the need for a leader and becoming the person he has to become, more out of opportunity, and then waiting to see what happens internally. [Oswald is] not just a villain."

Pullman admitted that he had enjoyed the opportunity to explore his character in depth over the ten episodes.

"I'm in a big part of it," he explained. "In that arc over ten episodes, you can make a different kind of character than you can in a two-hour movie."

He added that he is expecting Danes to be killed off in the final episode, but confessed that he is still uncertain of the character's ultimate fate.

"I haven't seen [episode] ten," he said. "I don't know how it's going to end, but I have a feeling that the lawyers have determined that I'm going to be gone!"

Torchwood: Miracle Day will air in July on BBC One in the UK and Starz in the US.